Microsoft Corp. today complained that the European Commission had forced it to hand over trade secrets to rivals, effectively giving them a “free ride” on the work the software maker did to acquire new customers and develop new technologies.

Microsoft is ready to put a stripped-down version of Windows on the market if it fails this week to persuade a judge to suspend a landmark EU antitrust decision.

Microsoft has appealed against the EU’s landmark antitrust decision at the European Court of First Instance, charging the ruling would undermine innovation and growth.

The EU’s competition chief expressed confidence today that his landmark decision against Microsoft would withstand a court challenge due this week, even as his US counterpart renewed criticism of the order.